Cavities are a type of dental hard tissue defect caused by bacterial infections. The factors leading to cavities primarily include bacteria, food, host, and time, mainly due to bacteria using food residues to produce acid demineralization in teeth, resulting in cavities. Cavities may also be due to incomplete enamel development during the prenatal calcification of teeth, which can occur if there is a calcium deficiency in the mother during pregnancy. Therefore, teeth are more susceptible to decay after they emerge, so cavities might be caused by a calcium deficiency during prenatal development. In addition, cavities are also related to postnatal factors, such as not brushing or rinsing promptly which allows food residues to remain, or due to the consumption of sweet foods, especially sugars, which bacteria break down to produce acids that cause tooth decay.